A battery-operated timepieces such as a wristwatch ceases to function as a timepiece when the voltage of a battery is reduced due to battery depletion. Therefore, such battery-operated timepieces often include the function of notifying a user of a reduction in the voltage of a battery.
For example, an electronic timepiece disclosed in Unexamined Japanese Patent Application Kokai Publication No. 2015-135347, which is a Japanese patent literature, is capable of changing a manner of rotating a second hand, thereby notifying a user of a reduction in the voltage of a battery. However, this notification enables the user to know only the reduction in the voltage of the battery at the time of the notification. Even if a previous usage status by the user is a cause of the voltage reduction, the user is incapable of knowing the cause.